Radio loud-speaker



March 26, 1929. I 1 KERSTEN 1,706,453

RADIO LOUD SPEAKER Filed March 28, 1927 2 Sheets-Sheet l Inufmfov Jacob Kwam March 26, 1929. J. KERsTEN RADIO LOUD SPEAKER 2 Sheets-Sheet 2 Filed March 28, 1927 In'uandv Jacob Kamafun n EE Patented Mar. 26, 1929.

UNITED STATES JACOB KERSTEN, OF KALAMAZOO, MECHIGAN.

RADIO LOUD-SPEAKER.

Application filed March 28, 1927. Serial No. 178,850.

rllhis invention relates to a sound amplifying and modulating construction designed to be used in connection with a radio loud speaker unit. lt is an object and purpose ot the present invention to inalie a device of this character in a siinpleand econ oinical manner, which will be attractive in appearance and with which blasting ot' sound at certain pitches thereot is obviated. ik iurtliei obj ect oil the invention iste provide a construction oi this character wherein. an ainplilying horn is not only housed vitliin an outer enclosing housing but it, with the housing, is mounted upon and carried by a-supporting base, all ot the parts being secured together by a very siiiiple and practical construction. The invention consists in inany novel constructions and arrangements ot parts going to inake up the complete device which will be liully understood from the `liollowing description taken in connection with the accompanying drawin gs, in which,

Fig. 'l is a front elevation oit the sound aniplilier.

Fig. 2 is an enlarged vertical section through the construction shown in Fig. l.

Fig. 3 is a fragmentary enlarged vertical section through the lower part of the construction illustrating the `nianner in which the horn and its housing are connected with the supporting base.

Fig t is a. horizontal section through the construction shown in Fig. l. the plane ot said section bein slightly above the center of the housing, and

5 an elevation of the amplifying horn vwhich is housedfwithin said housing.

Lilie reference characters reiter to like parts in the different figures ot the drawino's.

The horn which is used is inade of suitable inaterial including paper, plaster of Paris composition7 burlap and knitted fabric, the details et the process of construction oit which 'forni no part of the present invention. lt includes a vertical neel; l at its lower end, troni which the horn extends to one side and upwardly with the progressive enlargement as in dicatedfat 2, being thence turned back and considerably enlarged and terminating the spaced apart sides 3 and 4 connected by an integral curved portion 5, the lower edges 6 ot the sides 3 and l being located in a substantially horizontal plane. The open end ot the amplifying horn is ot large size and the edges G of said sides 3 and 4: lie in substan- `tially a horizontal plane.

that the outer sides ot the walls ot the neel;

coine substantially in alignment with the outer sides o' the sleeve 't' as best shown in Fig. 3.

rllhe housing in which the horn is located is niade of two parts 9 and l0 each of which is of conical torni. The side 9 is the rear oit the housing and the side l() the vtrent side. rlheirout side lt) has a iiuniber et openings cut therethrough in accordance witlr any predetermined artistic design and on the inner side ot the side l0 a screen 1l is secured, passing over the openings so as to inale a better api-carence. rlhe screen oit open inesh, that the sound waves may readily escape.

'llie edges ol the tivo sides 9 and l() ot the housing are brought together and the rear side 9 lies snugly against the rear side l ot the horn. Vln the saine niannei', those parts ol the vliront side l0, lett a'lfter the openings are cut therethrough press against the front side 3 oli the horn. L rod l2 threaded at bot-h ends passes through the centers ot and lie. between the conical sides 9 and l0 and at each end is equipped with a nut i3 ot' the Ytorin best shown in Fig. 9.. The rod lies iininediately underneath the lower edges 6 ot and t et the horn and serves to the sides e hold the enlarged portion or bell oi the horn in the upper part ot the housing; and when the nuts 13 are tightened. snugly to place, holds the horn in contact with the inner sides et the two parts 9 and l() et said housing.

A ring lo'li sheet inetal having U-shaped cross section is located around the contacting edge portions ot the two parts 9 and l() and clamped thereagainst holding` the said parts against separation. Ring la extends entirely around the liousii'` except at the lower side thereof, being parted at this point and having its ends closely adjacent to each side et the neck l where it iasses downwardly through an. opening in the lower side ot the housin The housing and horn, as thus assembled, are applied to a base which may be inade of Cil CII

wood or any other suitable material. The base includes an upper section 15 and lower section 16. The upper section 15 is suitably curved at its upper' edge and grooved to re ceive the lower side oit' the housing. It also has a vertical opening 17 therethrough tor the neck 1 and the sleeve 7 of the horn to pass through. The lower section 16 of the base has a large cylindrical recess 18 made therein upwardly from its lower side, the central vertical axis of which is substantially coincident with the axis of the opening 17.

lVhen the horn and housing have been applied to the base the sleeve 7 extends below the lower end of the vertical opening 17 and is then provided with a nut 19 screwed on the exterior threads of the sleeve, which nut fits in a recess 20 ot larger diameter than the opening 17 and at the lower end thereof. Accordingly, when the nut 19 has been applied and comes against the shoulder at the ripper side of the recess 20 it draws the horn downwardly against the rod 12 and in this manner draws the housing at its lower side downwardly against the upper section 15 of the base thereby iirmly securing all o1 the parts together.

In the recess 18 previously described the usual loud speaker unit 21 of any desired type is located the same being attached to the sleeve 7 by connecting an exteriorly threaded projecting sleeve 22 at its upper side with the interiorly threaded lower end of the sleeve 7 as shown in Fig. 3.

lVhen the horn is thus placed within and assembled with the housing and the base, a very lirm structure is produced and one incapable of excess vibration. The side 4 particularly ot the horn makes iirm contact with the side 9 of the housing and excess vibration which would produce blasting is eliminated, while the housing side 9 acts in a measure as a sounding board to amplify and modulate the sound emitted. This invention of an amplifier for loud speaking units has proved very practical and useful. Sound passing :from the mouth ot the horn is directed outward through the openings made in the Front side 10 oi. the housing. As before stated the tirm engagement ot the horn with the sides of the housing is a feature of the construction which is very desirable and necessary for the attaining oit the best results, making a substantial sound board which absorbs excess vibrations, eliminates blasting' and vibrates in synchronysm with the sound waves to properly reproduce, modulate and amplify the same. The construction also adapts itself tor an exceptionally practical assembly of the parts which go to make up the structure. The invention is delined in the appended claims and is to be considered comprehensive ot all forms of structure coming within their scope.

I claim:

1. In an amplifying horn, a vertical neck, a metal sleeve secured to said neck at its lower end to which a loud speaker unit is adapted to be attached, said neck being extended to one side and upwardly and progressively enlarged for a distance and then curved in a reverse direction and termed into a bell with :trent and rear sides having their lower edges lying in the same horizontal plane, said sides converging upwardly toward each other and also toward each other at their outer edges away from said enlarged portion ot the neck and integrally joined with each other.

2. In a construct-ion oit the class described, a housing comprising, two conical housing members having their base edges located against each other in a vertical plane, means lor securing said members together, the 'trent member having openings therethrough, and an amplifying horn located in the housing, having a neck extending through the lower side oit said housing and, within the housing being turned laterally and upwardly and enlarged progressively away from said neck and terminating in a relatively large bell having an open lower side, the front and rear sides oit the bell being shaped to lie against the inner sides ot said front and rear members ot the housing at their upper portions.

3. A construction c i ntaining the elements in combination defined in claim 2, said rear side oi" the horn where it engages against the rial' side ot the inner member olf the housing being cemented thereto, substantially as described.

4. An amplifying construction comprising a hollow housing, a horn located within said housing and having a neck extending through the lower side thereof, said horn being curved l laterally and upwardly away from the upper end oit the neck and enlarging progressively away from said neck and being thence curved back over the neck and formed into a relatively large bell having an open end, the lower edges of the sides ot said bell at said open end thereotI lying in the same horizontal plane, the front side ot' said housing having openings for the escape ot' sound, said tront side being located substantially at right angles to the plane of the open end of said bell.

5. In a' sound amplifier, a hollow housing having an opening in its lower side, a base having` a seat formed at its upper side against which the lower side ot the housing bears, a horn located within the housing and having a depending neck extending through the opening in the lower side ot the housing, said base having a vertical opening through which the neck also extends, means threaded on lto the lower end o1E the neck and against the base tor drawing the horn in a downward direction, and means extending through the housing under the upper portion oi the horn whereby when said horn is drawn downward ly the housing is also drawn downwardly against Said seat on the base.

6. In a sound ampliiier, a hollow housing having an opening in itslower side, a horn located within said housing having a neck extending through said opening in the housing, said horn being curved laterally and upwardly away from the upper end or' the neck and` enlarged progressively away therefrom and terminating in a bell filling the upper portion of the housing and having its lower edges located in a horizontalplane, a rod extending through and between the sides of the housing directly underneath the lower edges of the sides of said bell of the horn, a base formed at its upper side with a seat for the lower side of the housing and with a vertical opening therethrough through which the neck of the horn passes, and a nut threaded on to the lower end o the neck against Jthe under side of the base to thereby draw the horn downwardly against said rod and,

through said rod, draw the housing into firm engagement with said seat on the base.

7. In a sound amplifier, a housing comprising, a conical back member, a conical front member located with its base edges against the like edges of the back member, means for securing said housing members together at their' edges, said front member having openings therethrough, and a horn having an enlarged bell with an open lower side substantially iilling the upper portion of the housing and with its front and'rear sides hearing against the front and rear sides of the housing, said horn also having a neck portion extending downwardly and under said bell and through the lower side of the housing.

In testimony whereof I afix my signature.

J ACGB KERSTEN. 

